Evaluation of depth-dependent properties of municipal solid waste using a large diameter-borehole sampling method
John Hartwell1, M Sina Mousavi2, Jongwan Eun2
1SCS Engineers, Omaha, NE, USA.
Journal of the Air & Waste Management Association (1995)
|November 12, 2020
Summary
This study analyzed municipal solid waste (MSW) geotechnical properties and biological status using borehole sampling. Findings reveal consistent waste mass and provide insights into landfill compressibility and settlement processes.
Area of Science:
- Geotechnical Engineering
- Environmental Science
- Waste Management
Background:
- Understanding the geotechnical properties and biological status of municipal solid waste (MSW) is crucial for landfill design and management.
- Depth-dependent variations in MSW characteristics significantly influence landfill performance and long-term stability.
- Previous studies often lack detailed analysis of undisturbed MSW profiles at various depths.
Purpose of the Study:
- To analyze the geotechnical properties and biological status of undisturbed municipal solid waste (MSW) in relation to depth.
- To evaluate the compressibility and settlement characteristics of MSW based on its physical and biological state.
- To estimate the original height of the waste pile using the waste shrinkage ratio.
Main Methods:
- A large-diameter borehole sampling method was employed to extract undisturbed MSW samples from a 28 m deep borehole.
- Collected samples were subjected to laboratory experiments to determine moisture content, constituent characterization, unit weights, specific gravity, decomposition state, and saturation.
- Methane production tests and First-Order Rate Equation (FORE) analysis were conducted to assess biological activity and compressibility.
Main Results:
- MSW mass was found to be relatively consistent throughout the borehole depth and had not reached the accelerated methane production phase.
- Maximum total and dry unit weights at depth were determined to be 12.9 kN/m³ and 10.6 kN/m³, respectively.
- The original MSW pile height was estimated at 40.5 m based on the waste shrinkage ratio, and various compression parameters were evaluated.
Conclusions:
- The study successfully characterized the geotechnical properties and biological status of MSW with depth.
- The findings provide valuable data for understanding MSW compressibility and settlement, essential for landfill engineering.
- The large-diameter borehole sampling method proved effective for analyzing undisturbed MSW characteristics.
